/*
 * Copyright (C) 2009, 2010 Nick Johnson <nickbjohnson4224 at gmail.com>
 * 
 * Permission to use, copy, modify, and distribute this software for any
 * purpose with or without fee is hereby granted, provided that the above
 * copyright notice and this permission notice appear in all copies.
 * 
 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 */

#include <signal.h>

#include <rho/mutex.h>

/****************************************************************************
 * __sighandlerv
 *
 * Array of signal handlers. Protected by the mutex <__sigmutex>.
 */

sighandler_t __sighandlerv[SIGMAX];
bool __sigmutex;

/****************************************************************************
 * signal
 *
 * Registers a signal handler for the signal number <signum>. Returns the
 * old signal handler on success, SIG_ERR on error.
 */

sighandler_t signal(int signum, sighandler_t handler) {
	sighandler_t old;

	if (signum < 0 || signum >= SIGMAX) {
		return SIG_ERR;
	}

	mutex_spin(&__sigmutex);

	old = __sighandlerv[signum];
	__sighandlerv[signum] = handler;

	mutex_free(&__sigmutex);

	return old;
}
